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Catalytic converter

Hi - I own a VW Jetta 2003, and the check engine light keeps coming and the code it something about the catalytic converter. My mechanic just changed the O2 sensors about 3-4 months ago thinking this would fix it…well it hasn’t. He’ll turn it off every time I take it in and put some fuel cleaner in it, but it comes right right back on with in 10-20 miles. My question is, how important is it that I get this changed. Like most people I don’t have the money to spend 500-700 bucks on it! Can I just pull a “Homer Simpson” and cover the check engine light with electrical tape?



Bridget

Sure you can cover the CEL with electrical tape. But do you really want to? “How important is it that I get this changed” I guess it’s not important unless you plan on keeping the car and realize the longer you let it go, the more expensive it will get. The catalytic converter might have some more life in it, or it might be toast. What the light is telling you is that what the sensors are reading is not within range of what they expect to read. You’ve changed the sensors, (which apparently were not bad to start with), so you can rule them out. Now something else is causing the sensors to not read what they want to see. It could be a fuel or air problem or something else going on with another sensor upstream. Your cat could be worn out (especially if there is over 100K miles on car), or there could be something else causing the sensors to get their out of range readings, and if you change your cat without fixing the root of the problem, you could fry your new cat as well. If you don’t have a county or state emissions test, and you absolutely cannot afford to get it fixed, you can ignore the light with the understanding the worst damage you’ll probably do is ruin your cat and suffer bad gas milage. Now if your CEL starts blinking at you, that’s another whole thing. You’d want to pull over and get that fixed yesterday.

In addition to what benny stated, I want you to think about something else:

When the next problem crops up, how will you know about it if the CEL is already lit up?

When engine problems are not dealt with in a timely manner, the ultimate repair bill keeps getting bigger and bigger. Since you won’t know about the next problem when it begins, you will essentially be guaranteeing yourself that repair costs will really start to add up on this car and you will likely shorten the life of the car.